While I understand that praying with a Minyan is obligatory and one should do one’s utmost to do so, what is the status of this obligation when going on vacation? Flying in an airplane for a long flight? Going on dates (Shidduch) during the summer months in the evening when Mincha/Maariv is around 7:30/8:00 p.m.?

The Shulchan Aruch OC 90; 9 writes that one should make an effort to pray with a Minyan, the Mishna Brura ibid. 29 states that if one might lose money for praying with a Minyan he can pray on his own yet if it will only prevent him from making money – he should prefer the Minyan. The principal is that one should make maximum effort for a Minyan and if it's beyond your control – you are exempt. If a lack of Minyan will lose you your Shidduch or your flight – you can pray on your own.